Apple released a surreal missive on Friday morning that said the only thing wrong with the iPhone 4 is the way it calculates signal-strength bars. That letter is either an honest explanation or total bullshit — and it's high time that a competent, unbiased antenna-engineering team found out.
On the face of it, Apple's letter — …

@JeffyPooh

Either your antennae knowledge is non-existent, or you are very, very bad at explaining your point, but since you say that the voltage at the ends of an antenna are very high I have to assume the former.

The High Road

Apple should have said " Yeah there appears to be an issue" and then offer 50 USD gift certifcates toward a bluetooth headset or get real swank and quickly produce "limited edtion" Apple bluetooth headsets available for those who cry

A2DP

They would need to be A2DP at that and they would have to be white. I wonder how they wold get the dock connector to fit though. We all know that standards where you could buy something and they don't see any revenue never float at Apple.

Thoughts

My thoughts:

* The iPhone 4 is definitely more susceptible to attenuation as demonstrated by Anantech - crippling so, I don't think so

* Attenuation does indeed happen on every phone. On testing today, I've discovered that my old Sony Ericsson w800i experiences a drop of 20dB from being on the desk to picking up and holding "naturally", 25dB with a "death grip"

* The bars are demonstrably skewed the wrong way - a 20dB drop would have a devastating effect on this

Despite this coming across as defending Apple, I do believe that it is incredible that they've gone from denying all problems with it, to saying "ooh it's software" while not acknowledging that the aerial design is not the best idea they've ever had. It is rather insulting to say the least - but it's also PR spin.

Apple grants New York company free bumpers!

Out of 1.7 million consumers who bought the iPhone 4, only a few extremely special customers in New York were given free bumpers for their phones. Because they were located in an area where AT&T signals usually achieve 5 bars and in a spot where they can literally see a full line sight of the AT&T cellphone tower, the "grip of death" problem could still bring their signal from full strength to zero, zilch, nada! This is enough justification for Apple to give out free bumpers. So if you don't live near an AT&T cellphone tower, you're not special enough so don't expect to get free bumpers for your iPhone 4.

Apple will only support and give free bumpers to extremely loyal iPhone 4 customers that are located next to AT&T cellphone towers; the rest of millions of iPhone 4 owners are not loyal enough and can go suck an egg or use it's shells with gorilla glue it to cover the bottom right corner of their phone!

Insulting or Ignorant...

I'd say insulting. Hugely. Apple are treating its customers as if they are stupid. I love the functions of the iPhone, I love the Apps, and I love how it looks. But, from day one, even going back to the first iPhone in 2007, signal has never been its strong point. Back then, it was just about bearable and as a second phone I could live with it.

However this latest device has a very obvious flaw. Its been documented on videos on Youtube and many users, including myself, have experienced the fault, which results in not just a drop in signal, but in some situations a complete loss of data, awful call quality, or a dropped call.

Apple, in traditional arrogant style say, hey customers you are "holding it wrong", but if you are not happy we will "allow" you to return your device to get your money back. Gosh...wow, how generous. Still no apology for wasting our time due to your poor Quality Control process though and still no offer of a free bumper.

Sorry Apple, but I cant be so precious with my phone I have to treat it like some fragile doll when I hold it, its just so very very uncool. What next...a white Apple iGlove for holding the phone? All a bit 80s Duran Duran isnt it??

AND I'm left with a bad taste in my mouth. Its one thing for a manufacturer to release a product with a fault, none of us rational people think you are perfect, but its quite another to lie and treat your customers like something you stepped in.

Goodbye Apple, hello Google Nexus One. At least I can hold that any way I like...

Nexus one?

Simple, don't buy until they fix it...

I tried a 4G, it didn't wow me, when compared to my 3GS, yes I did look at the retina thingumy screen very carefully.

Then I read all this stuff about reception problems, and thought, maybe next year, iOS 4 I'll go for, maybe it will be nice to have multitasking, but this idea of putting it in a case or putting some duct tape on it, nah. If Android had a less clunky UI....

There's obviously a real problem there, and all this semantic jiggery pokery about signal bars and formulae can't cover for it. Maybe a good time to short Apple shares as they eventually get sued in the US and end up with a multi million dollar recall....

Fools Rush In

Um...

Not knowing anything about antenna design

I'm a little confused how Apple's claim that recalibrating the display of bars to better show bad signals is going to solve my problem' namely that holding my iPhone 4 in my living room sends the signal from O2's usual 2 or 3 bars to 'No Service'. The previous iPhone had no problems making or receiving calls at home, this thing drops at least half of them.

They're Not Fixing A Problem, ...

Caused by standard testing, plus Steve Jobs' curious ways

All of the RF testng of the device will have been on the bench. Quite possibly on uncased models.

It might even have been tested on a neat little stand, placed next to a cabbage, or a bucket of jelly, or some other way of simulating a human head. But the need to wire it up to the test system will mean that it was never checked in a real hand.

But, wouldn't Steve notice? No, because I suspect he holds his iPhone by the tips of his fingers, a quarter of an inch from his head. That way, he doesn't get greasy marks on his beautiful phone, and everyone can see him using his iProduct.

title

Nice, informative post there, one of the good ones....

... full of useful information.

Instead of sounding off, why not type in a little of your extensive experience of mobile device testing and product certification, with particular emphasis on the methodologies for testing interaction with the human body mass and other environmental sheilds?

I'd side with insulting...

I've got an iPhone 4 and I'm very pleased with it, but Apple's claims just don't hold up when you look at Anandtech's review where they "hacked" the install of the iPhone 4 to display dBm instead of the signal strength bars. The dBms clearly dropped when the phone was held "the wrong way" and it would eventually result in a lost connection.

If it was just a bars problem and not an aerial problem then surely the dBm reading should have only showed a marginal difference? A sudden plunge is hardly the sign of a software fault...

Only the true Messiah denies that he is the Messiah!

You can't escape physics

I'll try to keep this really simple, it's been said before but here we go again concisely:

Antenna efficiency can be compromised either by detuning or loss. Loss occurs when a 'lossy' object (such as a hand) comes between the transmitting antenna and the receiving antenna. This lossy object could be anywhere between these two, doesn't matter.

An antenna works most efficiently when it 'resonates' on the frequency that it is designed to work on, with a voltage peak normally at the extremities of the antenna. Proximity of your body to the antenna, it doesn't have to touch but the closer the more marked the effect, prevents this resonance and voltage peak. This is known as 'detuning' and has the effect of reducing radiation from the antenna by a very large degree.

All mobiles have to compromise aesthetics with technical function and in all cases the proximity of the body will cause a combination of detuning and loss, but, I fear, in the case of the latest iPhone the design allows the user to completely detune the antenna AND provide a lossy path to the receiving site, thus it is the worst of both worlds. A fundamental mistake which shows a total disregard of physics that CANNOT be corrected with software, so a bit of a fail I am afraid...

Lossy effect?

Sorry, No

Attenuation is an expected lowering of signal strength because of a known parameter and is a physical attribute of that device. Let's say, for ease of calculation, a certain dual conductor windowed signal transmission wire (ladder line) attenuation is -3db per 100 feet. Remember, -3db cuts signal strength in half. Knowing that parameter, you can calculate loss of signal strength for any give length. For instance. If your rig sends 200 watts RF into a -3db rated ladder line that's 100 feet long you know your antenna's radiator is "seeing" 100 watts since half of 200 is 100. The signal is attenuated basically by the "resistance" of the copper wire; the wire actually warms up a bit because of this.

"Lossy" is a condition whereby something is causing the antenna system to operate less well than it should. If that same ladder line is laying on the metal roof of your shack, or maybe has fallen on the wet ground, it will be "lossy". In effect signal will be bled off. But in this case, to get rid of the lossy condition, just get the ladder line off the metal roof and off the ground. That's why we have "stand offs" to keep certain types of line away from certain materials. The metal objects and the ground make the line lossy and the condition can be changed. Attenuation is a physical attribute and cannot be change by simple means. For copper wire you'd have to get into metalurgical changes in the R&D department.

Antenna Theory

Like I said, a little anntenna theory goes a long way. They may have really goofed and have the voltage standing wave ratio (VSWR or just SWR) greater than 1.5:1. If that's case, and the antenna is not resonant, and no software "fix" will solve the problem, it'll take a physical change. The same holds true for what you're saying. Maybe this is why Apple is currently seeking to employee three antenna engineers. You certainly don't need this level of engineering expertise to alter the signal strength display, but you do need the engineers to deal with inductive coupling problems of hand held devices.

I still say just come out with a full wave vertical polarized dipole in a headgear arrangement and settle it all. Maybe an end fed vertical similar to through the glass you see on vehicles. Or maybe even revert to external antennas. You just can't beat a resonant stinger in free space.

Re: Sorry, no again

Attenuation is the effect of lowering signal strength, whether by an expected factor or by a "lossy" condition. You are right, there is a difference between the the latter two, but the effect of both is, indeed, attenuation of the signal.

There is a physical attribute of any material which will result in attenuation, and the magnitude of it can be reliably measured. Just like there is a physical attribute of matter which results in friction. You won't find a physicist claiming that "friction is a physical attribute of matter," but that matter does have a physical attribute, called the coefficient of friction, which results in a measurable magnitude of resistance.

Likewise, "attenuation" is the physical effect of an attribute of a conductive material which measurably reduces signal strength.

Curious

Interestingly enough I have very rarely seen (here at Reg anyway) people repeatedly logging on to defend MS whenever they have effed up something (and that has happened quite often!) whilst one, understandably enough, sees a s*** load of highly critical postings. Hardly suprising, people get angry - justifiably angry. However, when Apple f*** up one sees that a large number of people will defend them to the last ditch, regardless. Anyone got an explanation for this phenomenon?

Re: Curious

>> "Anyone got an explanation for this phenomenon?"

Yes, it's not true. Read the posts, and count them: the overwhelming majority are just critical bashing. There may be a handful just stating "it works for me," which is hardly "defend[ing] them to the last ditch." Then there's a significant amount of those, like yours, who just like to remark things like "cue the fanbois," in spite of their absence.

This is consistent with any other forum on which Apple products or actions are discussed.

Because ...

.. The Sacred J has made himself "low hanging fruit". Whether they admit it, most people take a measure of satisfaction in seeing the self-proclaimed high and mighty layed low. Microsoft is s**t and we expect them to act like s**t so we've become accustomed to it. The Sacred J is usually right. But as my mate once asked me, "Had I rather be right or happy?". Apparently J has chosen to be right all the time and that generally makes you a target.

Re: Curious

True, but the converse applies too. When Apple do something that every other company out there does all the time without comment, you also see a large number of people rushing in to loudly criticise them. For whatever reason, Apple evokes very strong feelings among people. People either love to love Apple or love to hate them.

Halo effect

Yes...

What that means in practice is that people generally do not bother to defend MS, they simply begin to howl (quite right too!) when MS frakk up. I repeat, it is a strange contrast with the way some people react when Apple is critisised.

Really

Read my post again and then try and answer it properly. What I actually said, not what you thought I wrote. I talked about what one normally sees when MS gets a (deserved!) bashing. The fact that Mac-people are willing to defend regardless is an observable fact. Very few, except the brain-dead, are willing to defend MS in that way.

And

almost certainly some if not most of the rabidly anti-Apple comments one sees are knee-jerk reactions to the nauseating deference the fanbois flood whatever forum questions any aspect of this brand they've subsumed their self-images to.

Same happens with Ubuntu, of course. And with Microsoft, except that the Microsoft stooges are mostly to be found responding on the Microsoft-hosted forums and a few nominally-independent Windows-only blogs (that sports at least one all-but-resident Microsoft shill MVP).

shills

Both Apple and Microsoft have online shills, as do many other organisations today. I think that MS is just a little more careful with their deployment. Apple's problem is that they have traditionally viewed their customers as morons - the kind of people that have an aneurysm when faced with an error message, and those who like to define their very selves with consumer goods.

That worked out fine until the ipod and iphone, which suddenly had mass appeal beyond their normal moron target demographic. They haven't yet realised they're dealing with a different crowd now though, hence the steady stream of highly insulting garbage they pump out, and the asinine, transparent overdeployment of shills to try to "manage" public perception when it all goes tits up.

Attenuation and mismatch

Indeed it is called attenuation, and this happens when RF (radio frequency) signals pass through anything, even air has a small lossy effect relative to a vacuum. The body, as has been described by others, is mostly salty water, and therefore very lossy.

It's worth adding something about the 'detuning' effect I mentioned above; when your body detunes the antenna it affects it in two ways, firstly it changes the resonant frequency of the antenna which can drastically reduce radiation efficiency and secondly it affects the 'return loss' (sometimes known as 'VSWR' or 'voltage standing wave ratio). This is the (impedance) match between the transmitter circuitry and the antenna, and a poor match (high VSWR or low return loss) actually causes the RF power to bounce off the antenna back towards the transmitter, this 'bounced' power will either be absorbed by the circuitry and/or bounce back to the antenna, only to bounce back and forth (like an echo between two flat surfaces), eventually dying out, but, importantly, never actually radiating from the antenna.

To be fair to Apple, both of the effects I have mentioned (loss/attenuation and detuning) will be noticed in all mobile devices where the antenna is not in free space (closer than several wavelengths from the body or other lossy item). It's just that Apple have not made their lives easy by designing their antenna such that actual contact will cause the worst possible detuning by the body. Other manufacturers place their antennas behind an insulator (the case) and the detuning will be less, though still present when the hand is over or near it. The loss/attenuation effect will be similar to other phones.

I have tried to not make this too technical, but if I don't use the correct technical terms it seems I get pulled up. For my sins RF has been my job for over 30 years, so apologies if I have been too geeky!

How much is a 20 dB signal loss?

Thanks for the excellent explanation of attenuation and detuning. A question. From the reports we'e seen so far it seems this phone loses at least 20 dB of signal strength when being held in a typical left hand grip. What are normal figures for a standard phone? How much would you lose if you disconnect the antenna altogether? Could you give us some comparisons?

Testing?

Apple gives the impression of only testing the looks of a product, not actually giving it to people to use. If they had, this problem would have turned up, unless they all had deformed hands or apple gave them cases to stop them getting fingerprints on the wonderful new hardware.